Weight Converter

Enter a weight in either field and choose the units you want to convert between. The other value updates immediately.

You can edit either side, use Swap to reverse the conversion, and copy the result. The calculator also shows other useful units automatically.

The converter covers common metric units from milligrams to metric tonnes, together with pounds, ounces, and stone.

The table shows the relationship behind each unit and where you are most likely to encounter it.

Kilograms and pounds are one of the most common weight conversions. One international avoirdupois pound equals exactly 0.45359237 kilogram, which means one kilogram is approximately 2.2046 pounds.

The calculator uses the exact pound definition internally rather than the common 2.2 lb shortcut, so larger values do not accumulate unnecessary rounding error.

One stone contains exactly 14 pounds. A decimal stone value is useful for calculation, but body weight is often easier to read as whole stone plus the remaining pounds.

The converter therefore shows stone and pounds automatically for suitable values. For example, 11.5 stone can be read directly as 11 stone 7 pounds.

One pound contains exactly 16 avoirdupois ounces. For smaller weights, a mixed pounds-and-ounces result is often more readable than a long decimal in pounds.

For example, 2.5 pounds is exactly 2 pounds 8 ounces. The converter calculates this mixed format automatically when it is useful.

The oz option in this tool is the avoirdupois ounce used for ordinary weight and mass. One avoirdupois ounce equals exactly 28.349523125 grams.

A fluid ounce measures volume rather than mass, while a troy ounce is a different mass unit used mainly for precious metals. They should not be substituted for ordinary ounces.

A metric tonne is exactly 1,000 kilograms.

It is not the same as a US short ton of 2,000 pounds or an Imperial long ton of 2,240 pounds. This converter labels the metric unit as tonne and does not combine these different units under a generic ton option.

In everyday conversation, weight is commonly used when referring to kilograms, pounds, and similar units. Technically, these are units of mass.

In physics, weight is a force caused by gravity and is measured in units such as newtons. This calculator converts mass units; it does not calculate gravitational force.

The values below cover several common kilogram, pound, ounce, stone, gram, and tonne conversions.

The live converter keeps the full value during calculation before formatting the displayed result.

The metric relationships and the pound, ounce, and stone definitions used by the calculator are exact. Converted decimal results may still need to be rounded for display.

An exact unit conversion does not improve the accuracy of the original measurement. Scale resolution, calibration, and the precision of the entered value still matter.